Diagnostic and therapeutic exercise treadmill

ABSTRACT

An improved exercise treadmill is provided for diagnostic and therapeutic purposes, and which includes a heavy multi-ply nylon belt which is driven along and around a metal plate to define the walking area. The metal plate is composed, for example, of material of high heat conductivity, and it is coated with Teflon. This results in low friction and insures low drag, regardless of the weight of the patient. An advantage of the Teflon coating is that it does not require waxing. The aforesaid plate may be coated on both sides so that it may be reversed for extended use after the Teflon coating on one surface has become worn. Additionally, the metal plate is supported by a layer of resilient sheet material mounted on a platform to give the desired resilience to the plate.

United States Patent Hesen [72] Inventor: Joseph A. I-Iesen, Burbank,Calif.

[73] Assignee: Del Mar Engineering Laboratories, Los Angeles, Calif.

[22] Filed: Dec. 31, 1970 [21] Appl. No.: 103,155

[52] U.S. Cl ..272/69, 198/184, 128/2 R [51] Int. Cl. ..A63b 23/06 [58]Field of Search ...272/69; 119/29; 198/184, 193, 198/204 [56] ReferencesCited UNITED STATES PATENTS 1,082,940 12/1913 Flora ..272/69 3,280,96210/1966 Stone et a1 ..198/204 3,319,767 5/1967 Bretemitz et al......198/l84 X 3,198,319 8/1965 Blume ..198/204 3,181,690 5/1965 Jenkins..198/193 2,602,666 7/1952 Burke et al ..273/55 R 3,265,192 8/1966Stadelman ..198/204 3,590,980 7/1971 Bengtsson ..198/184 X zirszxeDIAGNOSTIC AND THERAPEUTIC EXERCISE TREADMILL 1 Nov. 21, 1972 PrimaryExaminer-Anton O. Oechsle Assistant Examiner-R. T. StoufferAttorney-Jessup & Beecher [5 7] ABSTRACT An improved exercise treadmillis provided for diagnostic and therapeutic purposes, and which includesa heavy multi-ply nylon belt which is driven along and around a metalplate to define the walking area. The metal plate is composed, forexample, of material of high heat conductivity, and it is coated withTeflon. This results in low friction and insures low drag, regardless ofthe weight of the patient. An advantage of the Teflon coating is that itdoes not require waxing. The aforesaid plate may be coated on both sidesso that it may be reversed for extended use after the Teflon coating onone surface has become worn.

Additionally, the metal plate is supported by a layer of resilient sheetmaterial mounted on a platform to give the desired resilience to theplate.

6 Claims, 3 Drawing Figures DIAGNOSTIC AND THERAPEUTIC EXERCISETREADMILL BACKGROUND OF THE INVENTION It has been usual in the prior artfor electrocardiograms to be taken of patients in a resting position ona table or bed. However, it has been found that a resting patient mayoften produce a normal electrocardiogram, even though there is clinicalor other evidence of occlusion. In order to overcome the limitations ofthe aforesaid resting electrocardiograms, clinicians have devised asimple two-step exercise test, so that the patient may be evaluatedunder mild stress. More recently it has been found that more conclusiveelectrocardiograms may be obtained if the patient is subjected to acontinuous exercise representing a constant workload which may be gradedat various time intervals.

The treadmill has proven to be the ideal instrument for the latterpurpose, and treadmill stress testing has become widespread in the artas a basis for a constant and accurate monitoring system, and for theevaluation of various physiological responses to steady state exercise.The treadmill also has the feature of reproducibility, simplicity andsafety, when used for stress testing.

Treadmill stress testing has many applications in the overall evaluationof heart disease, both as a diagnostic and as a therapeutic aid. Thetreadmill of the present invention is advantageous in that it isabsolutely safe, easy to operate, and capable of a long trouble-free,smooth-running and quiet operational life. The particular embodiment ofthe invention to be described, for example, exhibits smoothaccelerations even from miles per hour, and a smooth and non-jerkingvariable speed from 0 to miles per hour. The embodiment to be describedmay be operated at a fixed or variable elevation. It exhibits arelatively large walking area. It has adjustable gliders to provide afirm footing, and it is designed to have a space-saving configuration.The embodiment to be described also has a remote speed and elevationcontrol for the convenience of the physician.

Specifically, the design of the treadmill unit of the present inventionis such that the patient normally steps on and off the walking areawhile the aforesaid belt is stationary so as to preclude any possibilityof the patient stumbling. The unit exhibits a low profile further tofacilitate the ease with which the patient may step on or off the beltof the walking area. In addition, the unit to be described includes asturdy handrail which is comfortable to hold and which is positioned ata convenicnt height. The construction of the unit is sturdy and durable.

The elevation of the unit, as mentioned above, may be fixed or variable.For example, the elevation may be fixed at a 10% grade, or it may beadjustable manually or electrically from horizontal to a percent grade.An appropriate scale is provided on the instrument to indicate theelevation. The remote speed control may be positioned, for example, upto 12 feet from the treadmill in a constructed embodiment, so that thephysician may keep a close watch of the patient, the physician beingaided by various instruments. The control may also be mounted on theaforesaid handrail for operation by the patient in a therapeutic andrehabilitative exercise program.

A particular feature of the invention is in the walking area in which,as mentioned above, a heavy multi-ply nylon belt is provided which rideson a metal plate of high 'heat conductivity and coated with Teflon orequivalent material. This results in low friction, and it insuresminimum drag even for the heavier patients, as mentioned above. As alsopointed out previously herein, the Teflon surface does not requirewaxing, and the plate may be coated on both sides so that it may bereversed if required after extensive use. The metal plate also serves asa heat sink, due to its mass, high specific heat, and high heatconductivity, so that localized frictional heat build-up is held to alow level. That is, the metal plate is made of material, such asaluminum, having a high value of specific heat, and also a high value ofthermal conductivity, so as to serve as an efficient means ofdissipating heat, so that the local surface temperature rise due tofrictional heating is minimized.

In a constructed embodiment of the invention, for example, the speed isadjustable from 0-10 miles an hour, the elevation is adjustable fromlevel to 20percent grade, the walking area is of the order of 47 inchesX16 inches, the dimensions are of the order of 66 inches 21 inches, theweight is of the order of pounds. A l horsepower variable speed motor isprovided with a direct current speed control, and which may be energizedfrom the usual household alternatingcurrent mains. The foregoingspecifications are listed herein merely by way of example, and arenotintended to limit the concept of the invention in any way.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective representationof apparatus which may be constructed to incorporate the concepts of thepresent invention;

FIG. 2 is a second view of the apparatus of FIG. 1 with certaincomponents removed so as to reveal the internal operating elements ofthe apparatus; and

FIG. 3 is a cross-sectional view of the apparatus, taken substantiallyalong the line3-3 of FIG. 2.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENT As illustrated in thedrawings, the apparatus of the invention includes, for example, a frame10 of elongated rectangular configuration. The frame 10 comprises a pairof side rails 12 which are held in spaced and parallel relationship bytransverse rods, such as the rod 14. A pair of support pedestals 16 aremounted at one end of the frame 10, and a further pair of supportpedestals, such as the illustrated pedestal 18, are supported from theother end of the rectangular frame. The pedestals 18 are adjustable byan appropriate jack mechanism contained, for example, in a rectangularhousing 20, and the adjustment may be made, for example by means of ahand crank 22, or an appropriate electrical drive may be provided. Ascale 24 is provided on the side of the pedestal 18, so that apredetermined desired inclination may be obtained forthe frame 10.

A pair of rollers 26 and 28 are mounted at spaced positions on the frame10, as shown, and a metal plate 30 is mounted on the frame between therollers. As best shown in the representation of FIG. 3, the plate 30 issupported on a platform 32, and a layer of appropriate resilientmaterial, such as a felt pad 34, is interposed between the platform andthe plate. The resulting assembly is supported on the side rails 12 bymeans of appropriate bolts, such as the bolts 36.

The plate 30,- for example, may be composed of aluminum alloy, or anyother appropriate material of high heat conductivity. The platform 32may be composed of a selected appropriate grade of plywood, such as 0.75AD grade. The metal plate 30 is coated on its upper side withappropriate low friction material, such as Teflon; Du Pont No. 958 203black Teflon being appropriate for the purpose. It is preferable to coatboth sides of the plate 30 with the Teflon, so that the plate may bereversed in the event of wear of the upper surface of the plate afterextensive use.

An endless belt 40 is looped around the rollers and extends along theplate 30. The belt 40 is preferably a three-ply endless fabric beltcomposed, for example, of nylon. The top side of the belt istreated-with rubber to provide a friction surface, whereas the undersideis bare duct nylon ply, in the particular example, to minimize thefriction between the plate 30 and the belt.

An electric drive motor 50 is mounted at one end of the frame, as bestshown in FIG. 2, adjacent the roller 28, and between the roller and theend of the frame 10. The motor 50 is normally enclosed by a housing 52shown, for example, in FIG. 1, the housing also enclosing an appropriatecontrol unit 54 for the motor. The motor and the control unit may beenergized from the usual AC main through an electric cable 56, which isplugged into the side of the frame 10, as shown in FIG. 1. The motor 50is coupled, for example, to the roller 28 through a drive belt assembly58, which turns so the belt 40 is driven in the direction shown byarrows 3 in FIG. 2. I

The motor control unit 54 is under the control of a remote control unitshown as 60 in FIG. 1, and which is connected with the circuitry of thecontrol unit 54 through an appropriate electric cable 61. The remotecontrol unit 60 may conveniently be clipped by means of clips, such asthe clip 63, onto a handrail 62 which, in turn, is mounted inappropriate sockets 64 on the housing 52. The control unit 60 may beunclipped from the handrail, and mounted in some remote place, so as tobe controlled by the physician, rather than by the patient himself.

The remote control unit 60 includes an on-off switch, and a speedcontrol knob, as well as appropriate indicating instruments. A featureof the remote control unit is that the control of the motor 50 is suchthat the switch may be turned on, and yet the speed control may beturned down to a zero speed so as to permit the pa tient to step on andoff the belt 40 while it is stationary. When the patient has steppedonto the stationary belt 40, the speed control knob may then be turneduntil the belt starts to move, and this is achieved without any jerkingmotion which would tend to cause the patient to stumble.

As described above, the treadmill of the invention may be adjusted toany desired inclination, merely by turning the hand crank 22 until thedesired inclination is reached, as indicated, by the scale 24.

When the patient is on the belt 40, it moves smoothly across the plate30, by reason of the Teflon coating on the plate; Any heat generatedduring the frictional engagement of the belt with the plate is rapidlycarried away by the high heat conductive material of the plate. Afterperiods of extensive use, should the Teflon coating become worn, it is asimple matter to reverse the plate, so that the Teflon coating on theopposite side may be used. The platform 32 provides a firm support forthe plate, and the felt layer 34 provides a desired resilience betweenthe plate and the platform. Bolt and nut assemblies 36 as shown in FIGS.2 and 3 hold the plate 30 firmly in place on the frames 12 together withplatform 32 and felt layer 34. For safety and ease of assembly, the nutson nut and bolt assemblies 36 may be welded to frames 12, or caged nutsmay be used.

The invention provides, therefore, an improved therapeutic treadmillconstruction, which is fabricated to exhibit a low profile to facilitatethe ease with which the patient may step on or off the belt, and whichincludes a sturdy handrail which is comfortable to hold and which ispositioned at a convenient height. The invention additionally providesan improved construction, whereby the belt is supported on a firmsupport platform, the platform being constructed as an assembly so as toprovide minimum friction between the belt and the platform, and at thesame time to provide high heat conductivity so as to conduct away anyheat which may be generated by the engagement of the belt with theplatform. The drive motor of the apparatus is controlled, so that thereis a smooth speed control of the belt from zero to maximum speed, and sothat the patient need not step on or off a moving belt, nor need heattempt to stand on a belt subject to jerking motion.

The improved treadmill of the invention is safe and easy to operate, andit is capable of long trouble-free, smooth-running and quiet operationallife.

While a particular embodiment of the invention has been shown anddescribed, modifications may be made, and it is intended to cover allsuch modifications as fall within the spirit and scope of the inventionin the following claims.

What is claimed is:

1. Therapeutic exercise apparatus including: a frame having an elongatedrectangular configuration; a pair of rollers mounted at spaced positionson said frame; a metal plate of high heat conductivity supported on saidframe between said rollers and extending essentially from one of saidrollers to the other of said rollers; a coating of lowfrictionalmaterial disposed on at least one surface of said plate; a flat platformmounted on said frame under said plate and serving as a support for saidplate; a layer of resilient sheet material interposed between saidplatform and said plate; and an endless belt looped around said rollersand extending along the coated surface of said plate.

2. The apparatus defined in claim 1, in which said layer of resilientsheet material is composed of felt, and said platform is composed ofwood.

3. The apparatus defined in claim 2, in which said plate is composed ofaluminum alloy.

4. The apparatus defined in claim 1, in which said coating of lowfrictional material is composed of Teflon.

5. The apparatus defined in claim 1, in which said endless belt iscomposed of a multi-ply nylon fabric and which includes a rubberfriction coating on the outer surface thereof.

6. Therapeutic exercise apparatus including: a frame having an elongatedrectangular configuration; a pair of rollers mounted in spaced positionson said frame; a plate of high heat conductivity supported on said framebetween said rollers; a coating of low frictional material disposed onboth surfaces of said plate; and an endless belt looped around saidrollers and extending along the coated surface of said plate, in whichsaid plate is removable from said frame to permit reversal of said plateon said frame, and in which said coating is on 5 both surfaces of saidplate to double the wear life of said coating.

1. Therapeutic exercise apparatus including: a frame having an elongatedrectangular configuration; a pair of rollers mounted at spaced positionson said frame; a metal plate of high heat conductivity supported on saidframe between said rollers and extending essentially from one of saidrollers to the other of said rollers; a coating of low frictionalmaterial disposed on at least one surface of said plate; a flat platformmounted on said frame under said plate and serving as a support for saidplate; a layer of resilient sheet material interposed between saidplatform and said plate; and an endless belt looped around said rollersand extending along the coated surface of said plate.
 1. Therapeuticexercise apparatus including: a frame having an elongated rectangularconfiguration; a pair of rollers mounted at spaced positions on saidframe; a metal plate of high heat conductivity supported on said framebetween said rollers and extending essentially from one of said rollersto the other of said rollers; a coating of low frictional materialdisposed on at least one surface of said plate; a flat platform mountedon said frame under said plate and serving as a support for said plate;a layer of resilient sheet material interposed between said platform andsaid plate; and an endless belt looped around said rollers and extendingalong the coated surface of said plate.
 2. The apparatus defined inclaim 1, in which said layer of resilient sheet material is composed offelt, and said platform is composed of wood.
 3. The apparatus defined inclaim 2, in which said plate is composed of aluminum alloy.
 4. Theapparatus defined in claim 1, in which said coating of low frictionalmaterial is composed of Teflon.
 5. The apparatus defined in claim 1, inwhich said endless belt is composed of a multi-ply nylon fabric andwhich includes a rubber friction coating on the outer surface thereof.